<?php
//echo "welcome {$_POST["name"]},your email address is: {$_POST["email"]}";
?>

<?php 
//echo "welcome {$_GET["name"]},your email address is : {$_GET["email"]}";
?>

<?php
// define variables and set to empty values
$name = $email = $gender = $comment = $website = "";

if ($_SERVER["REQUEST_METHOD"] == "POST") {
   $name = test_input($_POST["name"]);
   $email = test_input($_POST["email"]);
   $website = test_input($_POST["website"]);
   $comment = test_input($_POST["comment"]);
   $gender = test_input($_POST["gender"]);
}

function test_input($data) {
   $data = trim($data);
   $data = stripslashes($data);
   $data = htmlspecialchars($data);
   return $data;
}
?>

<h2>PHP 验证实例</h2>
<form method="post" action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]);?>"> 
   姓名：<input type="text" name="name">
   <br><br>
   电邮：<input type="text" name="email">
   <br><br>
   网址：<input type="text" name="website">
   <br><br>
   评论：<textarea name="comment" rows="5" cols="40"></textarea>
   <br><br>
   性别：
   <input type="radio" name="gender" value="female">女性
   <input type="radio" name="gender" value="male">男性
   <br><br>
   <input type="submit" name="submit" value="提交"> 
</form>

<?php
echo "<h2>您的输入：</h2>";
echo $name;
echo "<br>";
echo $email;
echo "<br>";
echo $website;
echo "<br>";
echo $comment;
echo "<br>";
echo $gender;
?>


<?php 
$usernamerr = "";
$username = $note = $sports = "";
//POST这个一定要大写
if ($_SERVER["REQUEST_METHOD"] == "POST"){
	if (empty($_POST["username"])){
		$usernamerr = "username can't be null !";
	}
	$username = data_format($_POST["username"]);
	$note = data_format($_POST["note"]);
	$sports = $_POST["sports"];
}

function data_format($data){
	$data = trim($data);
	$data = stripslashes($data);
	$data = htmlspecialchars($data);
	return $data;
}
?>

<form action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"])?>" method="post">
username:<input type="text" name="username" />
<span style="color:red">* <?php echo $usernamerr ?></span>
<br>
note:<textarea rows="20" cols="20" name="note"></textarea>
<br>
<input type="checkbox" name="sports[]" value="篮球">篮球
<input type="checkbox" name="sports[]" value="足球">足球
<input type="checkbox" name="sports[]" value="乒乓球">兵乓球
<br>
<input type="submit" value="submit">
</form>

<?php echo "username : {$username}<br>note : {$note}";?>
<?php foreach ($sports as $value) {
	echo "<br>{$value},";
}?>


<?php 
echo "<br>";
$x = 5;
$y = 10;
function additition() {
	$GLOBALS['z'] = $GLOBALS['x'] + $GLOBALS['y'];
}
additition();
echo $z;
?>
